//#include <stdio.h>
//#include <conio.h>
//#include <math.h>
//
//double dydx(double);
//double dzdx(double, double);
//void EilerSolver(double, double, double, double, double);
//void main()
//{
//  EilerSolver(0,10,0,0.8,0.1);
//  getch();
//};
//double dydx(double y)
//{
//  return -0.5*y;
//};
//double dzdx(double x, double y)
//{
//  return 0.5*y-0.2*x;
//};
//void EilerSolver(double x0,double y0,double z0,double xn,double h)
//{double x,y,z,y1; int n,i;
//  x=x0;
//  y=y1=y0;
//  z=z0;
//  n=(xn-x)/h;
//  for (i=0; i<=n-1; i++)
//  {
//    y=y+h*dydx(y);
//    z=z+h*dzdx(x,y1);
//    y1=y;
//    x=x+h;
//  };
//  printf("\nSolved value Y=%g\nSolved Value Z=%g",y,z);
//};
